27.3.2023: Bug fixes, added support for sdfChoice (IPSO conversion tool)
2.9.2022: WoT Thing Model conversion tool was updated.
The Semantic Definition Format (SDF) is being developed to support Data Model conversions between different IoT ecosystems. The work was initiated at the One Data Model (OneDM) group in 2019. Please visit OneDM home page for more information.
The standardization of SDF is done in collaboration with the IETF in the A Semantic Definition Format for Data and Interactions of Things (asdf) Working Group. The current SDF Internet-Draft can be found from IETF datatracker.
On this experimental demo site, we have four different tools that are used to convert from different data models to SDF model and vice versa.
The IPSO Smart Object and MS Azure DTDL conversion tools are developed at Ericsson Research. If you have any comments or questions on these tools, please contact Petri Laari.
The Web of Things Thing model and YANG model conversion tools have been developed at the University of Bremen.
All the tools are available as open source:
The basic features are supported in all models and the conversion tools take into account the features defined in the current Internet Draft, but there are still some limitations. For example in the DTDL to SDF tool, complex schemas "Enum" and "Object" are supported, but "Array" and "Map" types are not yet implemented. The conversion tool development is currently ongoing.
Each ecosystem has their own ecosystem specific features that cannot be necessarily mapped one-to-one between all models. The support for such features is one task of the standardization work that is ongoing.
As one example, the DTDL Data Model has a "Relationship" -feature that allows defining arbitrary relationships between different objects. The basic SDF model supports only hierarchical relations between objects, but the conversion tool deployed on this web page supports also the newly proposed "sdfRelation" -feature which brings the same kind of functionality to SDF. This feature is targeted to be included in the next version of the SDF specification. This is implemented only in the SDF to/from DTDL conversion tool and it is not supported in other tools.
The current version of the tool expects only one field to be populated before pushing the "Convert" -button. Suggestion is to use either the automatic retrieval for SDF, IPSO, or DTDL, or then use the "Clear" before copying the source data model to the corresponding field.
The conversion process does support the basic features for all models, but there are some limitations.